Comprising around 8000 items, the collection falls into basically two types of record - medieval charters relating to the administration of Selby Abbey and its estates and later estate papers of the Boyle family, the earls of Cork and Burlington, and then the Denisons or earls of Londesborough.
U DDLO is by far the larger deposit and comprises the following: estate papers for the manor of Brayton (1485-1935), including court rolls 1485-1550, a 1638 list of pains and 19th century court rolls and jury verdicts; court rolls for the manor of Brayton and Thorpe Willoughby (1440-1615); the 1426 court roll for the manor of Crowle; manorial records for Eastoft (1318-1425), including the 1318 court roll, the bailiffs account rolls for 1356-61 and servants' accounts 1425-6; manorial records for the prebend of the prebendary of Fridaythorpe with Goodmanham (1707-1951), including court rolls, jury verdicts, surrenders and admissions; the same sorts of manorial records for the manor of Gannock (1772-1860), Goodmanham (1707-1896; including a 1776 survey of the allotments within the manor), Hambleton (1701-1952 including the sale in 1849 to Laura Petre of some closes), Hillam (1811-1951; including extracts of the will of the Reverend Thomas Chester of Lodsham); manorial records of Londesborough largely of the eighteenth century (1704-1874), including a case involving the earl of Londesborough about responsibility for waifs and strays circa 1705, a settlement certificate of William Cobb and his wife Alice of 1768 and a letter dated 1805 from Rowland Croxton to James Collins about the attendance of tenants at the Londesborough court; manorial records for Market Weighton and Shipton (1674-1951) divided into 1500 surrenders and admissions (1674-1897) and 800 jury verdicts (1714-1913) for the king's court and 1500 surrenders and admissions (1715-1908) and 800 jury verdicts (1705-1913) for the lord's court and miscellaneous records for both including accounts of fines received, four letters, the proclamation of the earl of Burlington at the opening of a fair in 1806 and an original bundle of papers relating to a case of the earl of Burlington against Thomas Worsley 1701-10 over the use of common land in Weighton and North Cliff; manorial court records for Middleton (1679-1945) including two letters from Suckling Spendlove to James Collins about a mortgage on a cottage in 1770 and the 1847 letter of Elizabeth Petch about the death of her husband who had been bailiff; manorial records for Monk Frystone (1815-1950), including an extract from the 1841 will of Richard Connell; intermittent court rolls from the manor of Monk Frystone and Hillam (1411-1671); call rolls and verdicts for North Dalton (1764-1857); the same for Nunburnholme (1750-1850); a small number of the same for Osgodby (1824-1856); court rolls for the manor of Over Selby alias Bondgate from 1399-1418 and then sporadically until 1552; manorial and miscellaneous records for Seamer (1743-1852), including jury verdicts, presentments and call rolls, the 1790 appointment of John Lockwood of Beverley as estate steward, a 1790 list of tenants and 1791 letter about estate boundaries and a copy of the 1809 enclosure case; court rolls and other manorial records for Selby cum Membris (1322-1950; these are very complete from 1322-1630); records for the manor of Selby (1522-1915), including 68 jury verdicts from the late 19th century; the court roll of Selby Waterhouses (1323-1374); two court rolls for Snaith (1458, 1521); manorial records for Thorpe Willoughby (1450-1913), including court rolls from the 1510s to circa 1550 and jury verdicts from the late 19th century; manorial records for Thwing (1722-1863) including call rolls and jury verdicts largely dating from the 1720s to the mid-19th century; court records for Tibthorpe (1774-1862); court records for Watton (1773-1857) and court records for Willerby (1810-1856).
U DDLO/20 contains the following account rolls for Selby Abbey: bursar (1431-1532, intermittent); pittancer (1403-1517, intermittent); abbot's proctor (1397-1398); kitchener (1412-1414, 1438-1439, 1475-1476); sacristan 1413-1414, 1494-1538, intermittent); extern cellarer (1391-1402, 1413-1414, 1489-1490); granger (1349-1350, 1404-1405, 1413-1432, 1474-1475, 1490-1491); infirmarer (1399-1403); chaplain to the abbot (1413-1414); almoner and keeper of the chantry (1434-1435); cellarer (1479-1480).
In addition, U DDLO contains a miscellaneous section at U DDLO/30 which includes 18th century drainage and navigation plans, late 19th century memoranda about the earl of Londesborough holding courts and a catalogue of property at Middleton on the Wolds, North Dalton, Shipton, Market Weighton, Goodmanham, Nunburnholme, Watton and Sutton Cranswick dated 1921.
U DDLO2 also contains largely manorial court records, most of them being very complete and unbroken for Brayton (1901-1935); Fridaythorpe with Goodmanham (1820-1851); Hambleton (1701-1952); Hillam (1855-1951; with a copy of the 1811 Hillam enclosure award); Market Weighton with Shipton (1714-1951); Middleton, court rolls (1772-1945) and minute books (1772-1853); Monk Frystone court rolls (1854-1950); for Selby, a court roll of 1554-5, a call roll 1699-1781 and a jury minute book 1780-99 as well as some miscellaneous account books and rentals (see further details below); court rolls for Over Selby/Bondgate (1520-1552); unbroken court rolls for Selby cum Membris 1673-1950 and court minute books 1772-1805; records for Thorpe Willoughby (1658-1950) including a court roll 1933-50 and a miscellany of earlier items. U DDLO2/12 is a section of miscellaneous items which includes early 20th century plans of the earl of Londesborough's East Riding and West Riding estates.